The present invention relates to a printer using a stencil which has a function of forming images carried on a plurality of documents in desired positions of a stencil, and a function of printing out a document image in a desired position of a printing medium even when the image formed in a stencil is in a reduced or enlarged scale.
A stencil cutting device capable of forming image information read from a plurality of documents in a single stencil is conventional and used with a printer operable with a thermosensitive stencil. Such a stencil cutting device may be implemented with a stationary platen to be loaded with a document. In this kind of device, so long as a plurality of documents to be read have sizes lying in an allowable range, their images can be formed in a single stencil in combination. Alternatively, the stencil cutting machine may be used in combination with a work station or a personal computer so as to edit the images of a plurality of documents or plurality of data on a display. Then a single block copy will be produced and used to cut a stencil. A block copy for cutting a stencil may be prepared by a traditional scissors-and-paste job, i.e., combining the images of a plurality of documents by paste and scissors. Apart from the editing scheme, a system is known in which a plurality of documents of relatively small size are arranged side by side and formed in a single stencil continuously, as disclosed in Japanese Patent Laid-Open Publication No. 21940/1990.
While the above-stated stationary platen scheme is capable of forming the images of a plurality of documents in a single stencil if their sizes are smaller than the maximum readable size, it cannot form images repetitively in a single stencil. The display scheme is not practicable unless the operator is an expert in the manipulation of a work station or a person computer. The scissors-and-paste scheme has a problem that when some document images have been accidentally omitted from the block copy, a new block copy has to be produced to repeat a stencil cutting operation. Further, the last-mentioned continuous cutting scheme is disadvantageous in that the maximum readable size is limited to the maximum stencil cutting size.
A printer capable of printing an image formed in a stencil in any desired position of a printing medium has also been proposed, as disclosed in, for example, Japanese Patent Laid-Open Publication No. 247164/1989. This type of printer reads the image of a document while transporting the document by document moving means to thereby cut a stencil, and prints out the image on a printing medium by using the cut stencil. The operating timing of the document moving means is automatically shifted to reduce the margin at the leading edge of a document, thereby shifting the image upward. As a result, the image position is maintained constant throughout all the printings. This kind of approach, however, causes the image of a document to be located in an unexpected position on a stencil and, therefore, on a printing when the image formed in the stencil is in a reduced or enlarged scale.